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3D-Printed Doll Prosthetic

My daughter’s doll lost a hand. After searching for a few days, she suggested I make her doll a new hand. My kids apparently think their dad can create and fix anything. While I had never attempted to create a solid model of a toy part, I was ready for the challenge.


I began with some geometric primitive shapes in Tinkercad, a 3D-modeling application. For the palm of the hand, I started with a sphere and extended that with a rectangular prism. The post that extended outward from hand to attach it to the arm of the doll was created with a cylinder and a torus wrapped around it. This cylinder jutted outward from the sphere, and the torus would allow for the hand to snap into the doll’s arm - if only my precise measurements were correct. I used a caliper to measure the post and hand dimensions of the right hand and reversed it for my left-hand model.


After building the solid model of the doll’s left-hand, I tweaked it and made adjustments to the dimensions. Trying to make it look a little more life-like, I added some curves to the palm by using another sphere shape to cut away at the rectangular prism. When I had a decent enough model, I began printing the doll’s prosthetic hand on a 3D printer with PLA filament.


It looks all right, and it fit even better than I had expected. It worked well and my daughter appreciated it. We had a good talk too about people and animals with prosthetics. It was a learning experience for us both.



Download or modify a 3D version of the solid model I created for my daughter’s doll hand here.

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